Various viewing aids exist to provide improved viewing of material on a viewing surface within a target field of view. Many such aids allow those with impaired vision to view printed materials (e.g., books and magazines), digital displays (e.g., LCD, LED, or other monitors), and photographs by creating magnified images of the material or images of the material with the color contrast and/or brightness changed. This may be useful for people with difficulty in reading, due to blurred vision, macular degeneration, or other vision impairments.
Existing viewing aids typically include a camera, and a viewing surface within a field of view of the camera. If the material remains at a fixed location on the viewing surface, then either the camera is moved relative to the viewing surface (and material), or the viewing surface (and material) is moved relative to the camera. If the material rests freely on the viewing surface, then the material itself may also be moved relative to the camera (and viewing surface). In either case, successive images of the material captured by the camera are either projected on a separate screen such as with CCTV systems, or on a display integrated with the camera.
For those viewing aids involving movement of the camera, the precision required to position the camera to capture images of the target portion(s) of the material may be difficult to achieve in many situations. This may be especially so if the material is printed material intended for reading, and even more so for those who have macular degeneration and need the image to be enlarged, and/or those with motor skill impairments and/or difficulty with hand-eye coordination. The same is true for those viewing aids involving movement of the viewing surface and/or material, as is done with X-Y tables.
Thus, it is desirable to have a viewing aid that allows enhanced viewing of material on a viewing surface, without requiring significant movement of the camera, viewing surface, or the material itself.